REVISTA
BRASILEIRA
DE
ANESTESIOLOGIA
PublicaçãoOficialdaSociedadeBrasileiradeAnestesiologiawww.sba.com.br
SPECIAL
ARTICLE
Comparison
of
three
different
insertion
techniques
with
LMA-Unique
TM
in
adults:
results
of
a
randomized
trial
Merih
Eglen
a,
Bahar
Kuvaki
b,
Ferim
Günenc
¸
b,
Sule
Ozbilgin
b,∗,
Semih
Küc
¸ükgüc
¸lü
b,
Ebru
Polat
c,
Emel
Pekel
daMalatyaStateHospital,DepartmentofAnesthesiologyandIntensiveCare,Malatya,Turkey
bDokuzEylulUniversity,MedicalFaculty,DepartmentofAnesthesiologyandIntensiveCare, ˙Izmir,Turkey cSamsunStateHospital,DepartmentofAnesthesiologyandIntensiveCare,Samsun,Turkey
dFlorenceNighthingaleHospital,DepartmentofAnesthesiologyandIntensiveCare, ˙Istanbul,Turkey
Received17December2015;accepted13July2016
Availableonline9August2016
KEYWORDS
Insertiontechnique; Laryngealmask; Supraglotticairway device
Abstract
Background: Thetriple airwaymaneuverinsertiontechniqueallowedfaster insertionofthe LMA.Thisstudycomparedthreedifferentinsertiontechniquesofthelaryngealmask airway-UniqueTM.
Methods:OnehundredandeightyASAI---IIpatientsaged18---65yearswereincludedintothe study.Patientswererandomlyallocatedtothestandard,rotationalandtripleairwaymaneuver (triple)group.Inthestandardgroup(n=60),theLMA(LaryngealMaskAirway)wasinsertedwith digitalintraoralmanipulation.Inthetriplegroup(n=60),theLMAwasinsertedwithtriple air-waymaneuver(mouthopening,headextensionandjawthrust).Intherotationalgroup(n=60), LMAwasinsertedback-to-front,likeaGuedelairway.Successfulinsertionatfirstattempt,time forsuccessfulinsertion,fiberopticassessment,airwaymorbidityandhemodynamicresponses wereassessed.
Results:Successful insertionatthefirst attempt was88.3% for thestandard,78.3% forthe rotationaland88.3%forthetriplegroup.Overallsuccessrate(definedassuccessfulinsertion atfirstandsecondattempt)was93%forthestandard,90%fortherotationaland95%forthe triplegroup.Timeforsuccessfulinsertionwassignificantlyshorterinthetriplegroup(mean [range]8.63[5---19]s)comparedwiththestandard(11.78[6---24]s)androtationalgroup(11.57 [5---31]s).Fiberopticassessment,airwaymorbidityandhemodynamicresponsesweresimilarin allgroups.
∗Correspondingauthor.
E-mail:[email protected](S.Ozbilgin). http://dx.doi.org/10.1016/j.bjane.2016.07.001
Conclusions:Rotational and triple airway maneuver insertion techniques are acceptable alternatives.Tripleairwaymaneuvertechniqueshowshigheroverallsuccessratesandallows shorterinsertiontimefor LMAinsertionandshouldthereforebekept inmindforemergent situations.
©2016SociedadeBrasileiradeAnestesiologia.PublishedbyElsevierEditoraLtda.Thisisan openaccessarticleundertheCCBY-NC-NDlicense( http://creativecommons.org/licenses/by-nc-nd/4.0/).
PALAVRAS-CHAVE
Técnicadeinserc¸ão; Máscaralaríngea; Dispositivo supraglótico
Comparac¸ãodetrêstécnicasdiferentesdeinserc¸ãocomamáscaralaríngea
LMA-UniqueTMemadultos:resultadosdeumestudorandômico
Resumo
Justificativa:Atécnicadeinserc¸ãousandoamanobratripladasviasaéreaspermitiuainserc¸ão mais rápida daML. Este estudocomparou três técnicas diferentes deinserc¸ão damáscara laríngeaUniqueTM.
Métodos: Foramincluídosnoestudo180pacientesASAI-II,entre18-65anos.Ospacientesforam aleatoriamentedesignadosparagruposdemanobradasviasaéreaspadrão,rotacionaletripla. Nogrupopadrão(n=60),amáscaralaríngea(ML)foiinseridacomatécnicadigitalintraoral. Nogrupo tripla (n=60),aML foi inseridacom atécnicademanobra tripladas viasaéreas (aberturabucal,extensãodacabec¸aeelevac¸ãodamandíbula).Nogruporotacional(n=60), aMLfoiinseridacomatécnicadeinserc¸ãodetrásparafrente,comoumacânuladeGuedel. Inserc¸ãobem-sucedidanaprimeiratentativa,tempodeinserc¸ãobem-sucedida,avaliac¸ãopor fibraóptica,morbidadedasviasaéreaserespostashemodinâmicasforamavaliados.
Resultados: Osucessoda inserc¸ãonaprimeira tentativa foide 88,3%para ogrupo padrão, 78,3%paraogruporotacionale88,3%paraogrupotripla.Ataxadesucessoglobal(definida comoinserc¸ãobem-sucedidanaprimeiraesegundatentativas)foide93%paraogrupopadrão, 90%paraogruporotacionale95%paraogrupotripla.Otempodeinserc¸ãobem-sucedidafoi significativamentemenornogrupotripla(média[intervalo]8,63[5-19]s),emcomparac¸ãocomo grupopadrão(11,78[6-24]s)eogruporotacional(11,57[5-31]s).Aavaliac¸ãoporfibraóptica,a morbidadedasviasaéreaseasrespostashemodinâmicasforamsemelhantesemtodososgrupos. Conclusões:Astécnicasdeinserc¸ãorotacionaledemanobratripladasviasaéreassão alter-nativasaceitáveis.Atécnicademanobratripladasviasaéreasapresentataxasmaisaltasde sucessoglobalepermiteumtempomenordeinserc¸ãodaMLe,portanto,deveserconsiderada emsituac¸õesdeemergência.
©2016SociedadeBrasileiradeAnestesiologia.PublicadoporElsevierEditoraLtda.Este ´eum artigoOpen Accesssobumalicenc¸aCCBY-NC-ND( http://creativecommons.org/licenses/by-nc-nd/4.0/).
Introduction
TheLaryngealMaskAirway(LMA)isausefulairwaydevice for airway management during general anesthesia and for emergencysituations. As an alternative airwaydevice the LMA is recommended for use during CPR because it isquicker andeasier toinsertthana trachealtube.1 The standard method of insertion described by Dr. Brain2 is relatively easy, but sometimes it is impossible to insert the LMA with the standard method. However ease and timeofairwaymanagementmaybeofspecialimportance in emergent situations. Since its inception the LMA has undergonevariousmodificationsintypeandmaterial,which havemadeothermethodsofinsertionpossible,quickerand easier than the standard method. Intraoral manipulation canputtheoperatoratriskoffingertraumaandinfection. However it is not possible to avoid intraoral manipula-tion when the standard technique or the classic LMA is used.Brimacombe andKeller3 showedthat insertion of a disposableLMAdoesnotrequireinsertionofthefingerinto
thepatient’smouth.TheuseofdisposablemorerigidLMAs isincreasingandmaybeotherinsertiontechniqueswillbe described for these LMAs in the future. We prefereither the triple airway maneuver or rotational technique when we useadisposableLMAinourclinic.4Thesearethetwo most favorable techniques among other anesthesiologists tooandtheydonotrequireintraoralmanipulation.3,5There ishowevernocomparisonofthesetwotechniqueswiththe standardtechniqueusingadisposableLMAintheliterature. Inthisstudywecomparedthreedifferentinsertion tech-niqueswiththeaimtofindtheeasierandfastermethodfor insertionofthedisposableLMA.
Methods
ComparisonofthreedifferentinsertiontechniqueswithLMA-Unique 523
intothisstudy.Patientswereexcludediftheyhadaknown difficult airway, mouth opening <2.5cm,body mass index >35kgm−2, or were at risk of aspiration. Age, gender,
weight, height, Mallampati grades were recorded at pre-anestheticevaluation.
Routine electrocardiogram, non-invasive blood pres-sure and pulse oximetry monitoring as well as Bispectral indexmonitoring(BIS-VistaTMAspectMedicalSystems,
New-ton, MA, USA) was applicated. Midazolam 0.02mgkg was administered at the beginning of pre-oxygenation. Anes-thesiawasinducedwithfentanyl1---2gkg−1andpropofol
2---2.5mgkg−1.AdequatedepthforLMAinsertionwasjudged
according to Bispectral index (BIS). Once BIS≤40 was achieved the LMA-UniqueTM (LMA-U, Intavent Orthofix,
Maidenhead,Berkshire,UK)wasinserted.Patientswere ran-domly allocated into one of three groups using computer generatedrandomnumbers:standard,rotationalandtriple airwaymaneuver (triple)group.Inallinsertiontechniques thecuff ofthe LMA wasdeflatedandLMA wasmoistened withsaline.
Additionalpropofoldosesof0.5---1.0mgkg−1were
admin-istered to maintain BIS value about 40 during insertion attempts. LMA size selection was according tothe manu-facturer’srecommendationsbasedonbodyweight.
Inthestandardgroup(n=60),theLMAwasinsertedusing thestandardmethoddescribedbyBrain.2Inthetriplegroup (n=60), the technique involved the following steps des-cribedbyKuvakietal.4:(a)holdingtheLMA-Uinthemiddle third of the tube between the indexfinger and thumbof thedominanthand;(b)performinga‘tripleairway maneu-ver’, the combination of head extension, mouth opening andjawthrust;(c)pressingtheLMAdirectly(front-to-back) againstthehard palateandpushingitalong theposterior palatopharyngeal curveusingthe indexfinger andthumb; (d)whentheindexfingerandthumbreachthemouth,the positionoftheindexfingerisadjustedsothatitpullsupward ontheinferiorsurfaceof thetube;(e)pushingtheLMA-U intoitsfinalpositionholdingtheshaft.Thisgroupisdefined originallyas‘‘direct’’techniquebutisdefinedas‘‘triple’’ groupinthisstudytoemphasizethetriple airway maneu-verwhichisnotperformedintheothertwogroups inthis study.4 In the rotational group (n=60), LMA wasinserted usingtherotationaltechniquewithout performingatriple airwaymaneuver.Stepsa,dandearethesame;however theLMA-Uwasinsertedback-to-front,likeaGuedelairway, and then rotated counterclockwise through180 as it was pushedintothehypopharynx.6
Alldeviceinsertionswereperformedbysame investiga-tors whowere experiencedin LMAuse andeach insertion technique. After insertion, the cuff was inflated with a manometer to fix intracuff pressure at 60cm H2O. The
number of attempts of LMA insertion and the time to achieve satisfactory first ventilation were recorded. The timebetweenpickinguptheLMAandobtainingfirst effec-tiveventilation (as evidenced byend-tidalcarbon dioxide waveformandsimultaneouschestmovement)wasrecorded as insertion time. Patients’ heart rates, and Mean Arte-rial Pressures (MAP) were recorded just before insertion of the device and at 1, 3, and 5min after the insertion. Anesthesia was maintained with O2, air and sevoflurane.
Any adverse events including desaturation (SpO2 below
92%),airwayobstruction,coughing,gagging,laryngospasm
and airway trauma (defined as presence of blood on removal of LMA) were also noted. Two attempts were allowed before insertion was considered a failure. When two attempts with one technique failed, any one of the othertwotechniques wasusedasan alternativeinsertion technique (at the discretion of the anesthesiologist). In caseofunsuccessfulLMAinsertion,trachealintubationwas performed.
Aftersuccessfulinsertion,fiberopticevaluationwas per-formedbyanobserverwhowasabsentduringinsertionof LMA.Theevaluationwasperformedbypassingafiberoptic endoscope (Fujinon Fiberscope NAP-SL, Fujinon Corpora-tion,Saitama, Japan)throughthe airwaytube toposition about1cmproximaltotheendofthetube.Thefiberoptic viewofthelarynxwasgradedaccordingtothescale:4=only vocalcordsvisible;3=cordsandposteriorepiglottisvisible; 2=cordsandanteriorepiglottisvisible; 1=vocalcordsnot seen.7
AttheendoftheproceduretheintracuffpressureofLMA wasmeasured andthereafterLMA wasremoved ina deep planeofanesthesia.OnremovaloftheLMA,theattachment of blood onthe surface of the LMA was noted.After the patientsstarted obeying commands, theywere shifted to recoveryareaandevaluatedfor sorethroatquantified on a10 point Numerical Rating Score (NRS), andagain after 24h.Anobserverblindedtotheinsertiontechniqueassessed thesedata.
The primary outcomes were to determine successful insertionoftheLMA-Uatthefirstattempt,insertiontime, fiberopticassessmentoftheairwayviewcomparingthree differentinsertiontechniques.Secondaryoutcomesas air-waymorbidityandhemodynamicresponsetoinsertionwere alsocompared.
Statisticalanalysis
Samplesizecalculationwasperformedbasedonthe assump-tionthattherotationalortripleairwaymaneuvertechnique wouldimprovethesuccessrateatthefirstattemptfrom75% to98%.With˛ of0.05andapowerof 80%,50patientsin eachgroupwererequired.Duetotheprobabilityoflacking dataandexcludedpatients,60 patientswererecruitedin eachgroup.
Theage,bodyweightandtimetosuccessfulLMA inser-tion,LMAusingtimewerecomparedusingone-wayANOVA. Sex,LMA size, numberof attempts at LMAinsertion, suc-cess rate and incidence of complications were analyzed usingchi-squaredtest.Heartrate,MAPandBISresponseto insertionofthedevicewerecomparedusinganalysisof vari-ance(ANOVA).Ap-value<0.05wasconsideredassignificant. Resultsareexpressedasmean±SD,mean(range),number orpercentage(%).Statisticalanalysiswasdone usingSPSS version15.0forwindows(Chicago,IL,USA).
Results
Table1 Characteristicsofpatientsinstandard,rotationalandtriplegroups.
Standard (n=56)
Rotational (n=54)
Triple (n=57)
p-Value
Male/female 23/33 29/25 29/28 0.37
Age;years 40.01±12.19 35.64±13.65 41.52±14.27 0.06 Weight(kg) 71.28± 12.22 71.83± 12.53 73.12± 11.79 0.71 Heigth(cm) 165.57±10.53 169.07±9.98 168.17±10.84 0.19
Mallampati(I/II) 40/16 48/6 48/9 0.05
Dataarenumber(n)ormean±SD.
13patientswereexcludedfromfurtheranalysisexceptthe successrates.Thegroupsweresimilarinage,sex,weight, height, ASA, Mallampati class, type and duration of the surgery(p>0.05).DifferentsizesofLMAwerealso compa-rableamongstthegroups(p=0.25).
Successfulinsertionatthefirstattemptwasnot statis-tically significant between the groups (Table2).Time for successfulinsertion was significantly shorter in the triple group(8.63s) whencompared withthestandard (11.78s;
p=0.0001)androtationalgroup(11.57s;p=0.001).Standard and rotational groups did not differ from each other (p>0.05).Noreactiontoinsertionoccurredinanypatient.
Resultsoffiberopticassessmentaswellasmorbiditywere similarbetweenthegroups(Table2).Ofthepatientswho hadsignificantamountofbloodontheLMAatremoval;five oftheeightpatientsinthestandardgroup,allofthethree patientsintherotationalgroupandfourofthesixpatients inthetriplegrouphadintranasalRhino-Dacryo-Cystostomy operation in which presence of blood onairway device is acceptable.
There was no significant difference between groups accordingtohemodynamicresponses(p>0.05).
Table2 End-pointsforLMAinsertiontechniquesandpostoperativeoutcomes.
Standard (n=56)
Rotational (n=54)
Triple (n=57)
p-Value
Timetosuccessfulinsertion(s)a 11.78(6---24) 11.57(5---31) 8.63(5---19) 0.0001b
0.001c
>0.05d
Successfulinsertionat1stattempt 53(88.3) 47(78.3) 53(88.3) 0.20
Overallsuccessratee 56(93.3) 54(90) 57(95) 0.55
Fiberopticview
4 27(48.2) 27(50) 23(40.4) 0.52
3 9(16.1) 14(25.9) 18(31.5)
2 15(26.8) 10(18.5) 13(22.8)
1 5(8.9) 3(5.6) 3(5.3) 0.68
Bloodonmaskatremoval
Noblood 43(77) 47(87) 43(75) 0.39
Traceamount 5(9) 4(7) 8(14)
Significant 8(14) 3(6) 6(11)
Patientsexperiencingsorethroat
None 53(95) 49(91) 52(91) 0.59
Mild 3(5) 4(7) 5(9)
Moderate 0 1(2) 0
Severe 0 0 0
Disphonia 0 1(2) 0 0.32
Disphagia 1(2) 0 1(2) 0.45
Dataaremean(range)orn(%).
aDefinedasthetimebetweenpickingupthelaryngealmaskairwayandobtainingfirsteffectiveventilationasevidencedbyend-tidal
carbondioxidewaveformandsimultaneouschestmovement.
b p-Valuebetweenstandardandtriplegroup. c p-Valuebetweenrotationalandtriplegroup. d p-Valuebetweenstandardandrotationalgroup.
e Definedassuccessfulinsertionatfirstandsecondattempt.
ComparisonofthreedifferentinsertiontechniqueswithLMA-Unique 525
Desaturation (SpO2 below 92%), airway obstruction,
coughing, gagging or laryngospasm was not seen in any patient.
Discussion
We have shown that in terms of insertioncharacteristics, airway complications and hemodynamic responses, the tripleandrotationaltechniquesmaybealternativestothe standard insertion technique. The triple technique makes itpossibletoinserttheLMAfasterthanwiththeothertwo techniques.
A questionnaire about LMA insertion showed that only 30%---34% of anesthesiologists favored the standard tech-niqueand36%---42%ofanesthesiologistsindicatedtheywere unwillingtousethestandardtechniqueofinsertion.5Cuff partial inflated insertion technique, rotational technique, andjawtrusttechniqueswerethemostfavoredalternative insertion techniques among the anesthesiologists partici-patingto thatstudy.According toauthors’ comment, the reasonofseekingdifferentmethodsistoincreaseinsertion successrate.
First time insertion success with LMA-U has been reportedtorangefrom77%to100%andoverallsuccessrate from93%to100%.3,8---13InsertiontimesfortheLMA-Uranges between14.7sand43s.3,12 Successrates forthreegroups in our study were consistent withthese results. Insertion timesforallgroupsinthisstudywerehoweverfasterthan intheliterature.
Inthecurrentstudythestandardtechniquesuccessrate was88.3%andincreasedto93.3%aftertwoattempts. Brima-combeBerry14 statethat ifthestandard approachis used correctlythefirsttimesuccessrateshouldbe95.5%inless than20s.Incontrasttothisstudywedidnotreachthisratio at first time insertion using any of our threetechniques. Similarlytherearesomeother studiesin whichsame suc-cessrateswerenotreachedeither.15---17Moreoverfirsttime insertionrateusingthestandardtechniqueintheliterature isreportedaslowas75%.18
Forrotationaltechniquefirsttimeinsertionsuccessrate was78.3%andincreasingto90%aftertwoattempts.When compared with the other groups a second attempt was neededinmorepatientsintherotationalgroup.Inourstudy withtheSoftsealTMLMA(SSLM,PortexLtd,HytheKent,UK)
wealsonoticedthatsecondattemptwasneededmorewith the rotational approach than with the direct technique.4 In another study first time successful insertion rate was reportedas86%.Butinthatstudyneuromuscularblocking drugwasusedtofacilitatetheinsertion.16InsertingtheLMA withitslumen facingbackward makesit easy toadvance over the smooth angle against the posterior pharyngeal wall.According toourexperiencethe other advantageof the technique is not requiring intraoral manipulation or assistance.Inchildrentherotationaltechniqueisassociated withhighersuccessratesforinsertionandlowerincidence of complication.19 Reported lower success rate in adults may be attributed to differences between pediatric and adultsairwayanatomyandtothebiggersizeoftheairway deviceinadults.
Fortripletechniquethefirsttimesuccessratewas simi-lartothestandardtechnique.Insecondattemptthesuccess rateroseto95%,thisdifferencewasnotstaticallysignificant
amongthe groups. However time for successful insertion wassignificantlyshorter in the triplegroup than the oth-ers.A differenceof 3s may notbe meaningful in routine practice,but it canbevaluable inemergentsituations of airwaymanagement.
Inourprevious studywiththeSSLMfirsttimeinsertion success ratewas98% and insertiontime was20s (8---56s) whenthe triple techniquewas used.4 First timeinsertion successratewashigherandmeaninsertiontimewaslonger thaninthepresentstudy.Sincemanyyearsweprefereither thetriple or rotationaltechnique whenwe have touse a disposableLMAinourclinic.Ourexperiencewiththese tech-niquesisgettingmoreeachday, whichmaybeareasonof evenfastertimesthaninourpreviousstudy.4Anotherreason forthisfindingmayduetodifferencesinthedesignand/or materialoftheLMAs.Thewiderandstifferairwaytubeand softercuffofSSLMmayberelatedwithhigherinsertion suc-cessrateswithtripleairwaymaneuverinsertiontechnique. In the literature there are some studies which compared LMA-UandSSLMaccording tothestandardinsertion tech-nique,andresulted withhigherfirsttimesuccessrates in theLMA-U group. In those studies insertion time of SSLM waslongerthaninsertiontimeofLMA-U.9,20
Ithasbeenrecognizedthatlungventilationisoften ade-quateandclinical signsof improperplacement arerarely observed even when the LMA is not in the optimal posi-tion.This was also the case in our study and ventilation throughtheLMAwasalwaysadequateinallgroups regard-lessofthefiberopticview.According toBrimacombeand Berry21studieddifferentinsertiontechniqueswiththe clas-sicLMAandhadanincidenceofepiglotticdownfoldingof 3.3%withthestandardmethodand7%withtherotational method.Goyaletal.have reported22 thethumbinsertion techniquewasaseffective as indexfinger insertion tech-niquewithrespecttoeaseofinsertionandinsertionsuccess. Contrarily,Krishnaetal.23 wereshowedtheLMAClassicTM
canbeinsertedsuccessfullywithouttheneedtoinsertindex fingerintopatient’smouth,thoughthefirstattemptsuccess rate is higher with the standard technique. In our previ-ousstudywithSSLMwehadanepiglotticdownfoldingrate of2%in thetriplegroup whereasthiswas6% inthe rota-tionalgroup.4 Inthisstudythiswas5%bothfor rotational andtriplegroups.Epiglotticdownfoldingwasdeterminedin morepatientswiththestandardtechnique.Aoyamaetal.24 found similar results according to down folding with the standardtechniquehoweverlowerincidencewiththetriple technique.Theyconcludedthatthetripleairwaymaneuver widenedthepharyngealspaceanddecreasedtheincidence ofdownfoldingof theepiglottis. Inthe abovementioned study,neuromuscularblockingagentwasusedfor facilitat-inginsertion.Sotheneuromuscularblockingdrugmayhave influencedtheplacementoftheLMA.Differentresultswith sameinsertiontechniquesmaybeexplainedwiththe inves-tigatorsexperienceoruse ofneuromuscularblockor with thedifferenceintheLMAtypes.
incidenceof patient movement in response toLMA inser-tion.ThereforewedecidedtokeepBISatalevelof≤40at thetimeofinsertion.Noneof thepatientsshowedairway reactiontoinsertion.Accordingtoourresults,insertingLMA withdifferent techniques did not produce any significant differenceinhemodynamicresponses.
Prevention strategiesfor sore throatinour studywere moisteningLMAwithsaline,allowingonlytwoattemptsand monitoring the cuff pressure. In a recent study it is sug-gestedthatmeasuringintracuffpressureafterinsertionof LMA reduced laryngopharyngeal complications by 70%. In thatstudytheauthorsrecommendtomeasureLMAcuff pres-sureroutinelyusingmanometeranddeflatingthepressure tolessthan60cmH2O.26
Inallpatientswhowereexcludedfromthestudy LMAs wereinsertedsuccessfullyusinganyofthealternative tech-niques.There wasnotanyintubationrequirement.This is confirming that if one technique fails, another technique maybesuccessfulfortheinsertionofLMA.Therefore anes-thesia providers should be able to master at least two alternativeinsertiontechniquesofLMA.
Therearesomelimitationsinourstudy.First,theLMAs wereinsertedbytwoexperiencedanesthesiologists.Maybe experienceinairwaymanagement,mayhaveaffectedthe results.Second, blindingwasnotpossibleduringinsertion oftheLMAandsotheinsertiontechnique,measurementof insertiontimeandnumber ofattempts.Third,becauseof ethicalreasonswedidnotabandonanalgesicuseandsointra andpostoperativeanalgesicusageswerenotquestioned.
Conclusion
We suggest that the rotational technique and triple air-way maneuver techniques are acceptable alternatives to thestandardtechniqueforinsertingLMAinadults. Consid-ering possibility of infection and trauma to the operator, rotationalandtripleairwaymaneuvertechniquesare advan-tageousbecausethesetechniques donotrequireintraoral manipulation.However triple airway maneuver technique showshigheroverallsuccessratesandallowsshorter inser-tiontimeforLMAinsertionandshouldthereforebekeptin mindforemergentairwaymanagement.
Conflicts
of
interest
Theauthorsdeclarenoconflictsofinterest.
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